New Jersey Toxics Workplan for NY/NJ Harbor Estuary Studies - Toxic

Project Objectives

The objective of this work is to determine the flux of sediment and contaminants crossing the head-of-tide in the 5 main tributaries to Newark Bay. These fluxes will be determined for base-flow and storm conditions, and will document the yearly loadings to the harbor from source located upstream of the head-of-tide.

Statement of Problem

Newark Bay and Hudson River are important port terminals in the northeast United States. These waterways require constant remedial dredging to keep them open for shipping. The sediments in these harbors, however, are known to be contaminated with polychlorinated biphenyl's (PCB's), dioxins/furans, poly-aromatic hydrocarbons (PAH's), metals, and other compounds. In order to reduce future need for dredging and disposal of contaminated sediment from the harbors, the sources of contaminants and sediment to each of the tributary rivers needs to be identified and removed. The NJDEP, in conjunction with the NYDEC, has undertaken a project to identify the sources and mass fluxes of sediment and contaminants to the labor estuary system including Newark Bay and the Hudson River.

Strategy and Approach

To determine fluxes in the main tributaries, sampling stations will be built near existing U.S.G.S. gaging stations at the head-of-tide on the Hackensack (at New Milford), the Passaic (at Little Falls, N.J.) the Raritan (at Bound Brook, N.J.), the Elizabeth (at Elizabeth, N.J.) and the Rahway (at Rahway) rivers. These stations will be equipped with automatic samples designed to collect samples of sediment and to ultra-low levels of dissolved organic and inorganic contaminants. Automatic samplers will collect discrete samples over time for total suspended sediment, dissolved and particulate organic carbon analysis, along with composite samples for mercury and cadmium (both dissolved and total metals) and dissolved PAH's. TOPS samplers, designed to collect sediment and water for trace organic analysis, will be used to produce time composite samples for that will be analyzed for 89 PCB congeners, 13 dioxin/furans, and 27 pesticide compounds. Before sampling begins, however, it will be necessary to calibrate the single point samplers used in the stations to traditional cross-channel sampling schemes such as equal width interval method. Suspended sediment, conductivity, and particulate organic carbon will be used to calibrate the stations.

Hydrologic data from the adjacent U.S.G.S. gaging stations will be combined with the chemical data produced to calculate event based fluxes and yearly loads to sediment and contaminants in each tributary. The sampling will be conducted during 7 storm events spaced over four seasons, and 2 baseflow events that occur during late summer and winter. Sampling at the head-of-the-stations will be closely coordinated with downstream estuary sampling being conducted by other researchers.